A movement of almost every object, such as a person, a horse, a board, a ski and a car, under gravitation is a series of waveforms with different lengths and amplitudes due to various changes in speed. In order to make a more realistic robot for virtual reality experience, in which a person can ride, it is basically necessary to independently control a speed, length and amplitude of the waveform and it is also required to form different types of waveforms by continuously controlling the speed, length and amplitude of the waveform in real time.
Conventional robots for virtual reality experience, which have been developed till now, mainly use a hydraulic cylinder. Almost of them can provide only directional characteristics, such as an ascent and a descent, using four or six axes. Thus, the conventional robots for virtual reality experience cannot provide the rhythms of changed waveforms. Further, there are some disadvantages in its high manufacturing cost and large size.